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171.
报道2013年冬云南滇西7个县(市)人工栽培石斛寒害灾情和灾后恢复情况;调查发现,不同石斛种抗寒性有很大差异,尖刀唇石斛、报春石斛、铁皮石斛寒害率较低,抗寒性强,而晶帽石斛、兜唇石斛、齿瓣石斛寒害率较高,抗寒性明显较弱。  相似文献   
172.
AIM:To explore the protective effect of emodin on lung injury induced by hepatic fibrosis in rats. METHODS:The hepatic fibrosis rat model was established with multiple pathogenic factors (CCl 4, ethanol, high fat, high cholesterol and low choline) and treated with different doses (20 mg/kg and 40 mg/kg) of emodin for 4 weeks. The hepatic index was measured. The biochemical indexes, endotoxin, homocysteine, albumin, aspartate aminotransferase,alanine aminotransferase, total bilirubin, total cholesterol and triglyceride, and hepatic fibrosis indexes, hyaluronic acid, laminin, collagen IV and procollagen Ⅲ, were detected. The histopathological changes of the liver were observed. The pulmonary index was determined. The histopathological changes of the lungs were observed. The levels of tumor necrosis factor α (TNF-α), malondialdehyde (MDA), nitric oxide (NO) and peroxynitrite (ONOO-) in the lung tissues were analyzed. RESULTS:The rat hepatic fibrosis model was successfully established. In model group, lung edema and inflammation occurred, and the pulmonary index and the levels of TNF-α, MDA, NO and ONOO- in the lung tissues were increased significantly. In emodin treatment groups, the pulmonary indexes were lower than that in model group. The pathological injury of the lung tissues was alleviated. The levels of TNF-α, MDA, NO and ONOO- in the lung tissues were decreased. CONCLUSION:Emodin has a protective effect on lung injury induced by hepatic fibrosis in rats.  相似文献   
173.
AIM: To evaluate the influence of maternal limb ischemic preconditioning (LIP) on the apoptosis of fetal hippocampal neurons induced by intrauterine distress-reoxygenation in rats. METHODS: Intrauterine ischemia was induced by clamping the uterine and uterine branch of the ovarian blood vessels with aneurysm clamps for a period of 15 min followed by removal of the clamps to permit reperfusion. Sprague-Dawley (SD) rats (n=12) were randomly divided into 4 groups on the 19th pregnant day: sham (S) group, LIP group, fetal distress (FD) group and LIP+FD group. The cesarean birth occurred on embryonic day 21 to obtain 12 fetal rats alive in each group. The fetal rats were decapitated and the pyramidal cells in CA1 hippocampus were observed under light microscope. The neuronal apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) staining and the apoptotic rate was calculated. The expression of Bcl-2 and Bax were detected by immunohistochemical method and Western blotting. RESULTS: The rates of neuronal apoptosis in FD group and LIP+FD group were significantly higher than that in S group (P<0.05), while no significant difference was observed between S group and LIP group (P>0.05). The expression of Bcl-2 and Bax in FD group and LIP+FD group was significantly higher than that in S group (P<0.05), while no significant difference was observed between S group and LIP group (P>0.05). The ratio of Bcl-2/Bax was lower in FD group than that in S group. Compared with FD group, the rate of neuronal apoptosis was significantly lower (P<0.05), while the ratio of Bcl-2/Bax was significantly higher (P<0.05) in LIP+FD group. CONCLUSION: Maternal limb ischemic preconditioning attenuates the apoptosis of fetal hippocampal neurons induced by intrauterine distress-reoxygenation in rats, which may be associated with the up-regulation of Bcl-2 expression.  相似文献   
174.
AIM:To observe the expression of tumor necrosis factor α (TNF-α) and nuclear factor κB (NF-κB) in the renal tissue of the rats with contrast-induced nephropathy (CIN). METHODS:Male Sprague-Dawley rats (n=96) were randomly divided into control group (n=48) and CIN group (n=48). The model rats in CIN group were intravenously injected with iodinated contrast media (76% compound diatrizoate injection,10 mL/kg), while the rats in control group were injected with the same volume of saline. Six rats in each group were sacrificed at 6 h, 12 h, 24 h, 48 h, 72 h, 5 d, 10 d and 15 d after intravenous injection, respectively, and the blood and kidney samples of the rats were obtained. The renal tubular injury was assessed by histological examination (HE staining). The expression of kidney injury molecule-1 (KIM-1), TNF-α and NF-κB at mRNA and protein levels in the renal tissues were semiquantitatively measured by the methods of RT-PCR and immunohistochemistry, respectively. The correlations between the expression of TNF-α, NF-κB and tubular injury score, KIM-1 expression in renal tissue of CIN group were analyzed. RESULTS:The levels of serum creatinine (SCr) and blood urea nitrogen (BUN) in control group were not changed between different time points (P>0.05). The levels of SCr and BUN in CIN group displayed significant increases at different time points (except 15 d) compared with control group (P<0.05). The renal tubular injury score in CIN group was significantly higher at all time points than that in control group (P<0.05). The expression of KIM-1, TNF-α and NF-κB at mRNA and protein levels up-regulated significantly at 6 h and the peaking of KIM-1 expression was at 24 h, while the peaking of TNF-α and NF-κB expression was at 48 h in CIN group. The expression of KIM-1,TNF-α and NF-κB was significantly increased in CIN group compared with control group except at 15 d (P<0.05). The expression of TNF-α and NF-κB at mRNA and protein levels showed close correlations with renal tubular injury score (r=0.843, 0.758, 0.743 and 0.707, P<0.05). The expression of TNF-α and NF-κB at mRNA and protein levels was also positively correlated with KIM-1 expression (r=0.863, 0.807, 0.839 and 0.855, P<0.05). CONCLUSION:The expression of TNF-α and NF-κB at mRNA and protein levels in the renal tissues of CIN group is up-regulated and is closely related with renal tubular injury, indicating that the inflammatory response is involved in the pathogenesis of CIN.  相似文献   
175.
AIM:To observe the effects of δ opioid receptor agonist DADLE on acute lung injury (ALI) induced by acute global cerebral ischemia-reperfusion in rats. METHODS:SD rats (n=30) were randomly divided into sham group, model (I/R) group and DADLE treatment group. Global cerebral ischemia-reperfusion model was established by a modified 2-vessel occlusion plus hypotension. DADLE (5 mg/kg) treatment was performed via the left jugular injection before reperfusion. After 120-min reperfusion, the pathological changes of the lung tissues were observed under light microscope and electronic microscope. The activity of superoxide dismutase (SOD) and malondialdehyde (MDA) level were detected. The partial pressure of arterial oxygen (PaO2) was also measured. RESULTS:In I/R group, widened alveolar septum, capillary dilatation and congestion, endovascular and perivascular cells in the lung with neutrophil infiltration, and significantly reduced type II epithelial cell surface microvilli, alveolar lumen cavity and trachea with serous exudate were observed. SOD activity decreased, but the MDA level increased. Compared with I/R group, the SOD activity increased and MDA level decreased in DADLE treatment group, with significantly reduced lung congestion, the degree of lung injury, and the infiltration of neutrophils. Compared with I/R group, the PaO2 and oxygenation index in DADLE treatment group were increased. CONCLUSION:Various degrees of pulmonary injury were observed in acute global cerebral ischemia reperfusion model. DADLE might have a protective effect on lung tissues of ALI in rats.  相似文献   
176.
ObjectiveTo review the immune response to anesthesia including mechanical ventilation, inhaled anesthetic gases, and injectable anesthetics and sedatives.Study designReview.Methods and databasesMultiple literature searches were performed using PubMed and Google Scholar from spring 2012 through fall 2013. Relevant anesthetic and immune terms were used to search databases without year published or species constraints. The online database for Veterinary Anaesthesia and Analgesia and the Journal of Veterinary Emergency and Critical Care were searched by issue starting in 2000 for relevant articles.ConclusionRecent research data indicate that commonly used volatile anesthetic agents, such as isoflurane and sevoflurane, may have a protective effect on vital organs. With the lung as the target organ, protection using an appropriate anesthetic protocol may be possible during direct pulmonary insults, including mechanical ventilation, and during systemic disease processes, such as endotoxemia, generalized sepsis, and ischemia-reperfusion injury.  相似文献   
177.
ABSTRACT:   The attacking potential of the scavenging amphipod Scopelocheirus onagawae on artificially injured hatchery-raised Japanese flounder Paralichthys olivaceus juveniles was investigated in relation to the degree of injury on the fish. All injured flounder juveniles were attacked by amphipods regardless of the degree of injury, while non-injured juveniles were not attacked. The attack by amphipods on the juveniles generally depended on the amount of glycine, a main feeding stimulant for the amphipod, released from the injury opening. The swimming ability of flounder juveniles was important to avoid the attack of amphipods. Furthermore, an area of injury allowing the amphipods to cling to the fish affects to the vulnerability of juveniles against the predation of amphipods. This study suggests that scavenging amphipods are potentially involved in the rapid reduction of the number of hatchery-raised juveniles.  相似文献   
178.
利用华南(广东、广西、福建)芒果种植区115个气象站1961−2016年观测资料,结合芒果寒冻害指标,采用加权综合评价法,确定种植区各气象站点的寒冻害危险性指数,建立寒冻害危险性指数与地理因子之间的多元线性回归模型,并基于GIS技术对华南芒果种植区寒冻害危险性进行区划。结果表明:华南芒果种植区寒冻害危险性与地理因子之间关系密切,总体呈现由沿海到内陆,寒冻害危险性逐渐变大的趋势,此外,随着纬度和海拔的增高,从南到北芒果寒冻害危险性程度也逐渐增大。轻度危险区主要分布在华南芒果种植区南部沿海地带及部分内陆地市的低海拔地区,占种植区面积比例为56.85%,该区域适合大规模种植芒果;中度寒冻害危险性区域主要分布在华南芒果种植区内陆中低海拔地区以及北部高纬度沿海地区,占种植区面积比例为37.03%;重度以上的寒冻害危险性区域主要分布在华南芒果种植区内陆高海拔地区,占种植区面积比例为6.12%。通过历史灾情和各县区年产量资料验证,区划结果与实际较为吻合,研究结果可为华南地区芒果的优化布局和防灾减灾提供参考。  相似文献   
179.
马飞 《现代农业科技》2014,(5):91-91,96
分析了小麦发生冻害的多种原因,并结合多年工作实践,提出了一些预防小麦冻害发生的对策,以促进小麦获得高产。  相似文献   
180.
分析了茶树冻害产生的原因,提出冻害发生的预防措施及冻害发生后的补救措施.  相似文献   
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